Industrial facilities often discharge particle or dust laden exhaust. Consequently, government regulations and standards regulate such exhaust. As a result, particle/dust collection or recovery systems, such as baghouses and cyclone separators, are used for the removal of the particles and dust before further processing of the exhaust, if necessary, and release to the atmosphere. For example, while baghouses remove particulate from the gas stream, the exhaust may also need to be treated to remove other non-particulate dangers such as sulfur dioxide, nitrogen oxides, volatile organic compounds, and carbon monoxide. The dust and gas conveyed to a baghouse or other similar air or gas filtering system are separated; the dust is separated and collected for disposal or later use while the cleaned gases are vented to the atmosphere or further processing.
Currently, baghouses are employed at many manufacturing facilities, stationary and portable, for cost effective compliance with emission requirements. The filters are generally two or more sided structures with a central opening. The baghouse operates by allowing the gas stream to pass through the walls of the filters, catching the particles on the bag's walls. Thus, if the flow of dirty air is from outside the filter (to the inside of the filter and out an outlet), particles will be caught on the outer surface of the filter. To the extent the filters have a mesh or screen size, particles larger than the mesh or screen size are caught on and in the exposed filter surface.
Other similar filtering processes such as fiber collectors and clean rooms operate in similar manners. These systems essentially collect particulate material and/or moisture from an incoming stream and separate the particulate or moisture from the cleaned gas stream. For example, fiber collectors are utilized in places such as cotton processing facilities to separate cotton fiber and dust from exhaust gas streams produced in the manufacturing facility. Clean rooms also utilize filtered gas streams, but instead of exhausting a cleaned gas stream to the ambient atmosphere, clean rooms often utilize filtered ambient atmosphere by removing particulate and moisture before exhausting the cleaned gas into the clean room.
As the above mentioned baghouses/filtering equipment operate, the particles begin to clog the filters and restrict, or choke, the flow of the gas stream. The phenomena occurs because particles will get captured in the filter's mesh and cling or hold to the mesh. As the particles collect/cling, they build up on the mesh structure itself and on other captured particles. The result of this build-up is the steady reduction of the mesh size or opening. This clinging process can continue until the mesh openings are totally blocked, preventing and choking the flow of any further gas (dirty air) through the filter walls. Accordingly filters must be properly cleaned or replaced regularly.